aligning a blade to the miter slot on a vintage Craftsman table saw

Good morning fellow woodworkers.
I've posted a couple of previous messages regarding a Sears Craftsman 10" contrator table saw, model number 113.29901.
I'm working on achieving improved blade alignment prior to beginning a mitered corner router bit storage box.
I've purchased a PALS kit to make achieving the blade parallel to the miter slot easier. The trunnion on this model table saw has three bolts on the rear of the trunnion, one centered between the other two.
My question is, once I've attached the PALS brackets I'm assuming I have to loosen the center bolt to correct the blade alignment? I thought that given a center bolt the trunnion would not come out of alignment. All the bolts are tight so I don't know if correct alignment was achieved years ago when the tool was assembled. Any thoughts for those of you have have installed a PALS and have a table saw model with 3 rear trunnion bolts.
Also, the instructions suggest filing the rounded ends of the trunnion to establish more secure contact with the LAPS brackets. Any suggestion as to the type of metal file?
As always, thank you for your comments, suggestions, and recommendations in advance.
I've had positive and useful recommendations to all my posted questions in the short period of being a member of this community.
Mark Mrsa

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Originally Posted by Mark Mrsa

I'm assuming I have to loosen the center bolt to correct the blade alignment? I thought that given a center bolt the trunnion would not come out of alignment. All the bolts are tight so I don't know if correct alignment was achieved years ago when the tool was assembled.

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First, I would scribe the location (or otherwise mark) the location of the trunion as a reference starting point. You can most likely install the Pals without loosening the center bolt. This should keep you in the ballpark without having to start to far from the original mounting position.
As far as filing down the casting, I would only do it if absolutely necessary. This surface needs to be flat and parallel to achieve a tight connection. It you do file it try to keep the surface parallel to the mounting face of the trunion.
You will need to loosen the center bolt to adjust if necessary, otherwise there is no movement possible.

You need to first check the alignment with a dial indicator attached to the miter gauge. This check will tell you if it needs to be aligned (Which it most likely does). Then install your pals kit per the instructions. Once again measure the alignment and determine how far and which way it is out of alignment. Then loosen all the bolts so the trunions can move. The front ones need to be able to move as well so you don't put the carriage in a bind. Make your adjustments using the PALS, checking the alignment after each change. Once you have it aligned where you want it slowly tighten al the bolts, checking the alignment frequently. I found on my Craftsman saw that the star lock washers had cut grooves in the trunion castings and would pull the trunions back to their original position each time I tightened the bolts. I finally rotated all the lock washers so the teeth were not in their original grooves and was then able to tight the bolts without problems.

The pals work great. These types of saws tend to go out of alignment quit easily. The trick is to change the bolts to a grade 5,( 3 lines in the head.) You can tighten the other ones but the bolts stretch and after a while the trunnions loosen up. don't leace the studs from the pals in change them out one at a time after the alignment is done.

I use a piece of 2 inch wide stock I cut it and then continue it to the back of the blade. If it cuts at the back you will know which way to move it. I switch miter slots and repeat the process..

I wish you success

I have the same saw Mark, and I just loosened the center bolt slightly and it adjusted just fine.

FWIW I didn't loosen it much; just cracked it slightly.

I found that I didn't have much room between the sheetmetal saw body and the PALS screw on the left side (right side when looking from the rear) so consider doing that. It didn't need much; 1/8" or so but it was enough to make it easier to get the hex wrench into the screw to adjust it.

This saw was my dad's and I grew up with it so it has a lot of emotional value. But it is generally a pretty good saw; with a good blade I've never had any issues with burning, etc.

So good luck with your project. Consider an aftermarket fence if you haven't already.

To Tom Henderson2 specifically, but to all others who have replied to my question:
With the Craftsman model 113.29901, it appears to be very difficult, if not possible, to loosen the front trunnion bolts without removing the table from the sheet metal cabinet. Please confirm whether this is an accurate assumption on my part.
Given this, when a PALS kit is installed do the front bolts need to be loosened? I'm assuming there is a middle (third) bolt securing the front of the trunnion also. Can just the rear bolts be loosened to do the alignment?
Thanks for your replies, they have been helpful.
Mark Mrsa

Tough luck Mark!
I had that Craftsman saw before I got my Unisaw.
I spent hours with a long stick tapping the trunion and checking the dial indicator in the miter slot.
Save your pennies and get a cabinet saw - easy to adjust.
John Jardin

Hi Mark-

I was able to get at one of the front bolts by reaching through the blade opening. The other one was a long reach from the back of the saw. I had to remove the drive belt and banged up my knuckles but was able to do it.

be sure to have the drive belt installed when you do the alignment as the weight of the motor pulling on the arbor will affect the alignment. Don’t ask me how I know.

Hope that helps.

Tom,
My further question is, with six trunnion bolts should I loosen all six or leave one tight? I can reach the front right and middle bolts if you are at the front of the saw.
I have installed the the LAPS kit and at this point, the blade of the blade appears to be off approximately 0.001".
If I loosen all front trunnion bolts instead of leaving one tight won't that make adjustment using PALS more difficult?
Your response would help with using the best technique and not have to experience the frustrations other have had. I tried to contact inline industries for their advice since they appear to specialize in older saw updates.
Mark

Quote:

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Originally Posted by Mark Mrsa

Tom,
My further question is, with six trunnion bolts should I loosen all six or leave one tight? I can reach the front right and middle bolts if you are at the front of the saw.
I have installed the the LAPS kit and at this point, the blade of the blade appears to be off approximately 0.001".
If I loosen all front trunnion bolts instead of leaving one tight won't that make adjustment using PALS more difficult?
Your response would help with using the best technique and not have to experience the frustrations other have had. I tried to contact inline industries for their advice since they appear to specialize in older saw updates.
Mark

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You want to loosen all six. If you leave one tight, that point becomes a pivot which may twist the bracket so it binds on the curved lugs that allow your saw to tilt.

Hello Mark-

first, if you are within 0.001 then you are plenty good enough.

The PALS unit gives you a fair bit of force, so nothing needs to be Really loose. I cracked all the bolts, left one of the front trunnions bolts a bit snugger than the others, (to act as a pivot point) and did my best to get things aligned.

I foolishly went through the entire process with the drive belt removed, and found that as soon as I reinstalled the belt the belt force pulled the arbor out of alignment.

so I did it again, this time with the belt installed. Much happier.

This was a rather tedious process for me; access to the trunnions bolts was difficult, and even getting the Allen key into one of the PALS screws was difficult to to the close proximity of the cabinet. So I found it very helpful to do it in short (5 to 10 minute) intervals…. Im working from home due to the pandemic, so I would make one adjustment, write down the result, then go back to work. Later in the day, make another adjustment, then go back to work, until I got it done.

this avoided the frustration and impatience that comes with the process, at least for me.

i used a dial indicator mounted off of the miter gauge as shown in John White’s book.

Be sure to align the fence as well. I used the same miter-gage mounted dial indicator.

my saw originally had a fair bit of arbor flange runout, which lead to blade wobble. So as part of my renovation I removed the arbor and had a machinist Chuck the arbor in a lathe and true up the arbor face. That reduced the wobble and improved cut quality significantly.

lastly, be sure you have a good drive belt…. If the motor is bouncing around it will jerk the arbor around and lead to poor performance. I’ve been delighted with the Fenner link-belt but any good Vee belt will work.

i hope this helps.